Cement and concrete work.



106. COMPOSITIONS, Q I ts.

COATING R PLASTIC.

EDWARD THOMAS, OF WORCESTER, MASSACHUSETTS.

CEMENT AND CONCRETE WORK.

L ALAII 958,336. Specification of Letters Patent. Patented May 1'7, 1910, No Drawing. Application filed November 29, 1909. Serial No. 530,387.

To all whom 'it may concern: will prove the most effective. The tem er- 55 Be it known that I, EDWARD THOMAS, a ature of the mixing water greatly a ects citizen of the United States, residing at the time necessary to make the cement collVorcester, in the county of -Worcester and loidal. At about 65 Fahrenheit nine minutes 5 State of Massachusetts, have invented an often suffices. Colder water requires more Improvement in Cement and Concrete Work, time and warmer water less. of which the following is a specification. It has been found that plaster mixed as My invention relates to cements of the above described works far smoother under the general nature of Portland cement and espetrowel and less cement is needed in mortar cially to rendering plaster and concrete made made with very sharp sand than ordinarily.

with these more waterproof, though other It has further been found that concrete comadvantages will be pointed out or be obvious posed of sand, cement and broken stone can to those skilled in the art. be rendered waterproof by mixing in this Y It is well known that Portland cement colloidal cement just as I have described the when agitated with many times its weight making of mortar above. Another great adof water for some time, becomes a flaky gevantage of my invention is that it adds a latinous precipitate that is greatly increased waterproofing agent without adding any in bulk. Cement treated in this way is foreign substance which will injure the setknown as colloidal cement and ordinarily ting power of cement or cause it to deteriwill not set except under pressure. Now I orate by lapse of time.

have discovered that if this colloidal cement I a aware that other olloids have been is mixed with untreated cement and water proposed as waterproofing agent, but many (with the addition of sand etc. if desired) of these, are known to detract from the the concrete when hard is waterproof in t ngth f th nt, a d it likely that practical work, though small thin test pieces th y 11 do, My inventio on th ntrary a e ofte ve y po usor e amp e n one adds to the strength of cement in the early Job to every gallon of water used was added stages f ha d m g, d th dd to th six ounces of cement, this was stirred till all usefulness f cement Thi l bl propthe cement had become colloidal. The water erty is shown the following table containing this colloidal cement was kept shows the comparative strength of briquets well stirred up and used for wetting a 1:3 i d i th di y, d th i d mixture Of untreated cement and sand. The by my colloidal process, The briquets were ult g l Was p as d 011 a l ky one to three sand and cement and broken at cellar wall (two coats each about inch th d t given i th tabl thick) and when hard the wall was found waterproof. Pumps were kept going in Plain Colloidal wells sunk just outside the wall so as to re waterwater lieve the water pressure during the plastering. lbs I have found by experiment that the great- 415 est bulk of colloidal cement is obtained when 443 not less than 4 and not more than 6 ounces avoirdupois of cement is used to each U. S. o 490 standard gallon of water. If more is used fvemgem 498 there is less colloid obtained. If more col- Six 5 Q23 23% loidal cement is wanted a second lot of 6 oz. 311'. 580 600 per gallon can be added after the first has Average 558 become colloidal, and this will increase the amount if stirred in the same way. Also I It has been found that cement which has have found that if certain substances are disbeen exposed to the air in very thin layers solved in the water before the cement is added will not always become colloidal and so cana more bulky mass of colloidal cement is obnot be used as I have described. Slag ce-' tained. In practical commercial work I bement seems to Work fully as well as true lieve about 2%% of common salt in the water Portland, but Rosendale or American natural cement sometimes fails to become colloidal, and when that is the case cannot be used in my process.

In the above the directions are given for the ordinary Portland cement of commerce containing sulfate of lime to regulate the setting.

While I have described what I believe the most practical method of work, various modifications can be adopted, such as filtering off the water and adding the colloidal cement separately to untreated cement or to a mixture containing untreated cement or to water that already contains colloidal cement. The colloidal cement must not be allowed to dry however.

What therefore I claim is:

1. A composition comprising colloidal cement and untreated cement.

2. A composition comprising colloidal cement, untreated cement and a filler.

3. The process of making mortar which l 3 H; c t;

T a/1A \5 b] lmh-H/ consists in adding cement to water, rendering the cement colloidal and adding the mixture' to untreated cement.

4:. The process of making concrete which consists in adding cement to water, rendering the cement colloidal and adding this cement to untreated cement and a filler.

5. The rocess of rendering cement colloidal which consists in agitating it in a dilute aqueous solution containing more than one fifth of one per cent. of matter adapted to modify the action of water on the cement.

6. The process of rendering cement colloidal which consists in agitating it in water till colloidal, adding more cement and agitating the whole.

In testimony whereof I have signed my name in the presence of two witnesses.

EDWARD THOMAS. Witnesses:

ALLEN C. THOMAS, LOLA M. Monnrs.

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